package com.kobeliu.netty.http;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import org.springframework.http.MediaType;

import java.net.SocketAddress;
import java.nio.charset.StandardCharsets;

/**
 * 自定义助手类
 * 创建自定义的http服务相应处理类
 *
 * SimpleChannelInboundHandler 相当于入站 入境的意思
 */
public class HttpHandler extends SimpleChannelInboundHandler<HttpObject> {
    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        System.out.println("handler注册");
        super.handlerAdded(ctx);
    }

    @Override
    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
        System.out.println("handler移除");
        super.handlerRemoved(ctx);
    }

    @Override
    public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel 注册=======");
        super.channelRegistered(ctx);
    }

    @Override
    public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
        super.channelUnregistered(ctx);
    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {

        System.out.println("channel===活跃");
        super.channelActive(ctx);
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel===不活跃");
        super.channelInactive(ctx);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel===读取完毕");
        super.channelReadComplete(ctx);
    }

    @Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {

        System.out.println("channel===用户事件触发");
        super.userEventTriggered(ctx, evt);
    }

    @Override
    public void channelWritabilityChanged(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel===可写更改");
        super.channelWritabilityChanged(ctx);
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        System.out.println("channel===异常捕捉");
        super.exceptionCaught(ctx, cause);
    }

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {

        //channel中读取
        Channel channel = ctx.channel();
        if(msg instanceof HttpRequest){
            //获得远端地址
            SocketAddress socketAddress = channel.remoteAddress();

            System.out.println("----------------------");
            System.out.println(socketAddress.toString());
            System.out.println("----------------------");

            //定义消息
            //通过缓冲区定义发送的数消息 读写数据都是通过缓冲区进行数据交互的
            ByteBuf content = Unpooled.copiedBuffer("hello Netty~", StandardCharsets.UTF_8);

            // 构建http response
            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1,
                    HttpResponseStatus.OK,
                    content);

            //为响应增加数据和长度
            response.headers().set(HttpHeaderNames.CONTENT_TYPE, MediaType.TEXT_PLAIN_VALUE);
            response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());

            //把响应的数据写到缓冲区
            ctx.writeAndFlush(response);
        }
    }
}
